PEX migrating 2.7.4 permissions Help

Hello

I am trying to use PEX with my permissions 2.7.4, as i saw you could migrate your permissions into it by typing commands in.

i have done the commands; /pex backend p2compact
/pex dump file permissions.yml
/pex backend file

i have changed nothing in the config. all it seems to do when i do the commands is add the people who are currently online, into a default group.

is there something that i need to change for it to migrate my 2.7.4 permissions into its permissions.yml

sorry if that sounds stupid or something, but i have always used permissions 2.7.4 with yeditor without error and now yeditor doesnt work for me. so i need a way to promote members ingame.

Thanks